1. Field of the Invention
The present invention relates to a user interface. More particularly, the present invention relates to an apparatus and method for controlling an interface according to a motion that a mobile terminal has made.
2. Description of the Related Art
Currently, electronic devices such as TVs, MP3 players, Portable Multimedia Players (PMPs), smart phones, and the like are equipped with a variety of input/output devices in order to enable a user to conveniently control the electronic device.
Among these input/output devices, the utilization of smart phones has recently increased exponentially. The proportion of devices using touch panels is rapidly growing in the market of mobile terminals, including a portable phone, a smart phone, and a laptop. As touch screen panels are expected to gain more popularity, the market for touch screens for mobile terminals will be rapidly boosted. Touch screen panels are also widely used in electronic appliances such as TVs or refrigerators. The market of electronic appliances will likely rank second in adopting touch screen panels, following the mobile terminal market.
Recently, extensive research has been made on recognition of a user's intention and action based on visual information, for natural interaction between a user and a touch screen. Typically, a user-friendly user interface is configured to recognize a gesture input by a finger or a touch pen. The trend of user interfaces is now shifting from an interface that operates according to a single finger-based single touch input on a touch screen to an interface that operates according to a multi-finger-based multi-touch input on a touch screen.
A touch screen is includes a plane (e.g., substrate) for sensing an input and a plane serving as a display. Therefore, a user's intention can be analyzed and perceived from a multi-touch input on the touch screen and the analysis and perception result may be output on the touch screen. A multi-touch-based user interface is designed in such a manner that the number of finger touches/pen touches on the touch screen and an associated operation are recognized and an associated command is executed. The interior structure of a mobile terminal supporting multi-touch input is described below.
FIG. 1 is a block diagram of a mobile terminal supporting multi-touch input according to the related art.
Referring to FIG. 1, the mobile terminal includes an output unit 101, a controller 103, a memory 105, and an input unit 107.
The output unit 101 outputs an image (such as a drawing or a Web page) on a touch screen. The image such as a drawing or a Web page is stored in the memory 105. When the image is output on the touch screen, a user may enlarge or shrink the image using the input unit 107 according to user selection. An intended part of the image displayed on the touch screen may be enlarged or contracted by touching the intended part with two fingers simultaneously. A touch pen may be used instead of fingers. Upon input of multiple touches through the input unit 107, the controller 103 controls the output unit 101 to display the multi-touched area enlarged or shrunk on the touch screen.
An exemplary operation performed upon input of multiple touches in the mobile terminal having the configuration illustrated in FIG. 1 is described below.
FIGS. 2A and 2B illustrate an exemplary operation performed upon input of multiple touches according to the related art. The operation is specifically for enlarging a specific area by multiple touches on a touch screen.
Referring to FIG. 2A, a user touches the touch screen 201 with two fingers 205 in a pinching motion to enlarge an image of a car 203 displayed on a touch screen 201. The enlarged area may be different depending on a position at which the two fingers 205 touch. Referring to FIG. 2B, the car image 203 is enlarged by spreading out the two fingers 205 on the touch screen 201. The degree to which the car image 203 is enlarged may depend on the distance between the two fingers 205 spread apart from each other.
While only the operation for enlarging an image is illustrated in FIGS. 2A and 2B, the enlarged image may also be shrunk using the two fingers 205.
According to the related art, the zoom-in or zoom-out ratio of a predetermined part of the touch screen may be adjusted only by pressing a predefined zoom-in or zoom-out key or making multiple touches. When a user wants to move from one page to another page or from one part to another part on the same page, the user is supposed to press a predefined move key or touch and drag an area of the touch screen. This means that for continuous zoom-in and zoom-out, the user should make consecutive key inputs or continuous multiple touches. In addition, to move from a specific part of a page to another part of the same page, the user should input keys successively or make continuous touches-and-drags, which the user may find inconvenient. Therefore, it is difficult to quickly and accurately perform a user-intended operation simply with an input on the touch screen or a gesture drawn on the touch screen.